MACKEREL RELATIVE is a term used to describe three different species of fish that are closely related to the mackerel. The first is the WAHOO, which is a large, fast-swimming fish found in tropical and subtropical waters around the world. The second is the BONITO, which is a smaller, schooling fish found in temperate and tropical waters. Lastly, the TUNA is a large, migratory fish found in temperate and tropical waters. All three species are popular for recreational fishing and are also used as food sources.